The city has “plenty” of flu vaccine – for now, Mayor Bloomberg said yesterday.

But that could change quickly if panicked New Yorkers flood doctors’ offices this week looking for protection against the worst outbreak of flu in years, city health officials admitted.

“We think we have plenty,” the mayor said yesterday, the day after the nation’s two flu-vaccine makers announced that they’ve shipped every last dose – more than 83 million shots.

Clinics across the flu-stricken nation are reporting they’re out of medication – but the mayor said “in New York City . . . you’ll find most doctors and clinics still have the vaccine.”

A spokesman for the city Health Department admitted no one knows exactly how much of a stockpile the city has – or how long it will last.

“We won’t have an accurate picture of our vaccine situation until Monday,” said Health Department spokesman Sid Dinsay. “But as of now, there is not a citywide shortage.”

The flu outbreak – which has claimed the lives of 11 kids, mostly in Colorado – has been less severe in New York.

But the federal Centers for Disease Control said Friday that the city is seeing more flu activity than in years past – an announcement that sent shivers through the health-care community.

“It will translate into more deaths,” Dr. Gregory Poland, head of the Mayo Clinic’s Vaccine Research Group, told The Post.

Poland said the flu would prove more deadly this year because the season started earlier – in late September, rather than November – and because the virus has mutated into a potent variety called A-Fujian. “This is a novel virus,” he said.

Nationwide, about 36,000 people die each year from the flu – but Poland said the death toll would probably double.